Here, Ricardo is in a clothes shop. He asks the attendant, Carla, if he can have a white shirt - uma camisa branca.
He also asks for something else - um chapéu. This means "a hat". We've come across the words for "a". These are called, properly, "indefinite articles" (as opposed to the words for "the", which are called "definite articles"). This is because the word "a" or "an" is indefinite - it doesn't specify which shirt or hat. Let's have a look at this table.

A/AN

A/AN

SOME

SOME

Masculinesingular

Femininesingular

Masculineplural

Feminineplural

um

uma

uns

umas

Some examples? Sure.

o gato e um gato - the cat and a cat

os pêssegos e uns pêssegos - the peaches and some peaches

a casa e uma casa - the house and a house

as árvores e umas árvores - the tree and some trees

Quickly, what does that e mean by itself? Simple - e means "and". Let's have some practice.

Convert the following from "the" to "a" or "some

1. Os sapatos = ______ sapatos (some/the shoe)

2. As gravatas = ______ _________ (the/some ties)

3. A saia = ______ _________ (a/the skirt)

4. O chapéu = ______ _________ (the/a hat)

Answers

1. uns

2. umas

3. uma

4. um

Another major word we need to get to know is Quero. This word means "I want". Of course, there are other conjugations...

Também means quite simply "also". So we have "Do you want also a black shirt?". But what on earth is this phrase, o senhor? Well, we've already learnt that você is more polite than tu. However, there is another level of politeness used in Portuguese. This form of "you" is used with people you don't know well, or people you have to show respect to, like bosses or teachers. Basically, this form allows you to refer to people indirectly. So rather than address someone directly by name or with a pronoun such as "você", you address them as if you were addressing a third person, "o senhor" ("the gentleman") or "a senhora" ("the lady"). This added distance makes the speech more polite. Take note, however, that this form of "you" changes according to the gender of the person you're talking to, plus how many people you are talking to as well!